Generally, an image forming apparatus includes a unit mounting portion capable of mounting/detaching a supply unit containing a developer. Furthermore, the image forming apparatus may include a tag reader that performs short-range wireless communication with an electronic tag through an antenna. The tag reader includes the antenna for short-range wireless communication.
Generally, the antenna is a coil antenna composed of a metal foil printed in a coil shape on a substrate. The substrate is provided to the unit mounting portion. Meanwhile, the electronic tag is mounted on the supply unit. The tag reader reads, for example, information about the color, the type, and the like of the developer from the electronic tag.
In addition, when the distance between the antenna and the electronic tag is short, an auxiliary antenna for reducing the resonance frequency of the electronic tag is known to be mounted to the supply unit.